An A-Frame is a piece of furniture used in the BDSM/Fetish/Kink community and lifestyle.  It works very similar to a whipping post or St. Andrew's Cross.  It is a triangular frame that can be anything from 6 to 7 feet tall.  It has a concave which means there is a space inside the triangle. A submissive or slave would be positioned here for activities such as bondage and domination. A submissive or slave's  wrists are usually tied up and immobilized using ropes, chains or other forms of restraints. The  ankles of the submissive or slave can also be bound or tied to the Frame. This is done to increase vulnerability and humiliation. It can be made from various materials such as aluminium or wood. In many instances rings are attached down the sides of the frame.  Ropes, chains, handcuffs and other restraints can then be clipped into or tied to the frame, thereby rendering the submissive or slave totally helpless and at the mercy of the Dominant in that play session. This can be a very erotic and sensual experience or for those who are interested or into pain and humiliation, it can be extremely rewarding to hand over total control and submit to caning, whipping, flogging, which are just a few activities practiced in BDSM. An A-Frame can also be built to incorporate suspension bars or hooks. The most common use for this would be shibari or rope play.